Just a quick copy and paste from my blog. Have a look there to see my wheels in GK1.
I found this on NASIOC though so GK1 is also STI gold for '05. Prodrive gold is a slight shade lighter than regular STI BBS gold.
F9657 2002 STI Dupont Gold
DG 4J1 2004 STI Gold
PMS 871 Prodrive Gold
GK1 STI Gold